Germanium layers

Physical Properties. Raman spectroscopy is an excellent tool for investigating stress and strain in many different materials (see Materlals reliability). Lattice strain distribution measurements in siUcon are a classic case. More recent examples of this include the characterization of thin films (56), and measurements of stress and relaxation in silicon—germanium layers (57). 

Interface states played a key role in the development of transistors. The initial experiments at Bell Laboratories were on metal/insulator/semiconductor (MIS) stmctures in which the intent was to modulate the conductance of a germanium layer by applying a voltage to the metal plate. However, only - 10% of the induced charges were effective in charging the conductance (3). It was proposed (2) that the ineffective induced charges were trapped in surface states. Subsequent experiments on surface states led to the discovery of the point-contact transistor in 1948 (4). 

If the germanium layers are partly oxidized by a short potential step to -1500 mV, random worm-like nanostructures form, healing in a complex process if the electrode potential is set back to more negative values (Figure 6.2-15). 

Fig. 6.7 SEM image of a germanium deposit, obtained upon elec-trodeposition under a GeU crystal at -1000 mV vs. Ge. The surface is completely covered by a thin germanium layer. A collection of nanoclusters with a grain size of about lOOmn is obtained.

Fig. 4 1.1. Schematic diagram of a FTIR instrument 1 moving mirror 2 fixed mirror 3 beam splitter made of KBr or Csl as supporter coated with a thin germanium layer. ADC analog-digital-conve rte r...

Figure 6.2-23(a) shows the STM picture of an about 100 nm thick silicon layer that was electrodeposited at —1600 mV vs. Fc/Fc, probed under potential control with the in situ STM. Its surface is smooth on the nanometer scale and its topography is similar to that of a germanium layer of comparable thickness [79]. Figure 6.2-23(b)... 

The window thickness and inactive germanium layer thickness. 

Figure 8. The amplitude of oscillation versus square root of ion-cnergy dependence for two multilayer systems consisting of silicon and germanium layers 2 nm and 3 nm thick, respectively.

Using the same UTL zeolite, Kirschhock and coworkers proposed the theoretical concept of inverse sigma transformation by removal of the germanium layer followed by calcination and generated a new zeolite structure experimentally (shown in Fig. 15) [132]. Since the D4R... 

Fig. 5.6.7 Reflectivity (solid curve) and beamsplitter efficiency (dashed curve) of a germanium layer on a potassium bromide substrate.

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